--- zzzz-none-000/linux-3.10.107/Documentation/devicetree/bindings/spi/spi-bus.txt	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/Documentation/devicetree/bindings/spi/spi-bus.txt	2021-02-04 17:41:59.000000000 +0000
@@ -55,9 +55,21 @@
     		chip select active high
 - spi-3wire       - (optional) Empty property indicating device requires
     		    3-wire mode.
+- spi-lsb-first   - (optional) Empty property indicating device requires
+		LSB first mode.
+- spi-tx-bus-width - (optional) The bus width(number of data wires) that
+                      used for MOSI. Defaults to 1 if not present.
+- spi-rx-bus-width - (optional) The bus width(number of data wires) that
+                      used for MISO. Defaults to 1 if not present.
+
+Some SPI controllers and devices support Dual and Quad SPI transfer mode.
+It allows data in the SPI system to be transferred in 2 wires(DUAL) or 4 wires(QUAD).
+Now the value that spi-tx-bus-width and spi-rx-bus-width can receive is
+only 1(SINGLE), 2(DUAL) and 4(QUAD).
+Dual/Quad mode is not allowed when 3-wire mode is used.
 
 If a gpio chipselect is used for the SPI slave the gpio number will be passed
-via the cs_gpio
+via the SPI master node cs-gpios property.
 
 SPI example for an MPC5200 SPI bus:
 	spi@f00 {